COF packaged semiconductor

1. A semiconductor device comprising: a multilayer laminate that includes a thermally stable, flexible polymer film, the laminate having a top surface and a bottom surface; a semiconductor die having a top surface and a bottom surface, the die's bottom surface contacting the laminate's top surface, and having substantially vertical sides oriented substantially perpendicular to the die's top and bottom surfaces; a molding compound contacting both the laminate's top surface and the sides of the die, but not the die's top or bottom surfaces, the molding compound having a first surface that contacts the laminate and a second surface and having sides oriented substantially perpendicular to the molding compound's first and second surfaces, a first portion of those sides contacting the die and a second portion of those sides not contacting the die; and a heat dissipation member that comprises: a heat conductor having a thickness approximately equal to the thickness of the second portion of the sides of the molding compound, comprising a material selected from the group consisting of silicon, molybdenum, and aluminum silicon carbide, and contacting substantially all of the die's top surface, and a heat spreader, having a surface area exceeding the molding compound's surface area, that contacts the heat conductor and the second surface of the molding compound and that comprises a material selected from the group consisting of copper and aluminum.

2. The semiconductor device of claim 1 wherein the film comprises a polyimide.

3. The semiconductor device of claim 1 wherein the molding compound comprises an epoxy, and wherein the heat conductor is bonded to the die using a high conductivity adhesive that comprises a gold eutectic.

4. The semiconductor device of claim 1 further comprising a plurality of solder balls that are attached to the laminate's bottom surface.

5. A flip chip-on-flex integrated circuit assembly comprising: a multilayer laminate that includes a thermally stable, flexible polymer film; a semiconductor die having an active surface and an inactive surface, the active surface including a plurality of contacts; a molding compound contacting both the laminate and the die, but not contacting the die's active or inactive surfaces, the molding compound having a first surface that contacts the laminate and a second surface and having sides oriented substantially perpendicular to the molding compound's first and second surfaces, a first portion of those sides contacting the die and a second portion of those sides not contacting the die; and a heat dissipation member that comprises: a heat conductor having a thickness approximately equal to the thickness of the second portion of the sides of the molding compound and a coefficient of thermal expansion that is greater than about one-half and less than about double the coefficient of thermal expansion of the die, the heat conductor contacting the die's inactive surface, and a heat spreader, having a surface area exceeding the molding compound's surface area, that contacts the heat conductor and the second surface of the molding compound and that comprises a material selected from the group consisting of copper and aluminum.

6. The flip chip-on-flex integrated circuit assembly of claim 5 further comprising a plurality of solder balls that are attached to the laminate.

7. A semiconductor device comprising: a multilayer laminate that includes a thermally stable, flexible polymer film, the laminate having a top surface and a bottom surface; a semiconductor die having a top surface and a bottom surface, the die's bottom surface contacting the laminate's top surface, and having substantially vertical sides oriented substantially perpendicular to the die's top and bottom surfaces; a molding compound, having a first surface that contacts the laminate's top surface and a second surface, the molding compound contacting the sides of the die, but not the die's top or bottom surfaces, and having sides oriented substantially perpendicular to the molding compound's first and second surfaces, a first portion of those sides contacting the die and a second portion of those sides not contacting the die; and a heat dissipation member that includes a heat conductor that contacts substantially all of the die's top surface, and a heat spreader that contacts the heat conductor and the molding compound's second surface, wherein the heat conductor has a coefficient of thermal expansion that is greater than about one-half and less than about double the coefficient of thermal expansion of the die, and wherein the heat spreader comprises a material selected from the group consisting of copper and aluminum and has a surface area that exceeds the molding compound's surface area.